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With the rapid advancements of portable and wearable devices, high-efficiency electromagnetic interference (EMI) shielding materials are highly required to eliminate radiated electromagnetic pollution. Ti3C2Tx MXene has shown great application potential as an EMI SE material due to its good conductivity. However, a single-loss mechanism has many limitations. Herein, to enrich the electromagnetic-wave-loss ways, MXene@ZIF-67/multiwalled carbon nanotubes (MWCNTs) composite films were successfully prepared by vacuum-assisted filtration, combined with the introduction of magnetic ZIF-67 anchored on MXene by an electrostatic self-assembly method. The MXene@ZIF-67/MWCNTs composite film (MZ2M8) achieved the best EMI shielding performance of 63.6 dB at 32 μm thickness, and the contribution ratio of the scattering parameters for absorption to reflection, i.e., SEA to SET, was 66.94%, thus achieving high absorption loss. Due to the high aspect ratio of the MWCNTs and the densely stacked "brick–mortar" layered structure, the composite film also exhibited excellent flexibility and mechanical performance, in which MZ8M2 could deliver a high tensile strength of 115.2 MPa, ensuring practical applications in different environments. Moreover, the thermal conductivity of MZ2M8 reached 3.367 W m−1 K−1, realizing the synergistic effect of high shielding efficiency and heat-dissipation performance, and avoiding the phenomenon of heat accumulation caused by the conversion of electromagnetic waves into heat energy. [ABSTRACT FROM AUTHOR]

To meet the increasing desire for a means of powering wearable and portable devices, the development of high‐performance flexible aqueous rechargeable lithium‐ion batteries (FARLIBs) would be greatly desirable. The design of binder‐free cathode materials with 3D architectures is the key to develop FARLIBs. Herein, self‐standing 3D Ni‐doped LiMn2O4 (NLMO) nanosheets are successfully prepared assembled by nanowall arrays (NWAs) directly grown on carbon cloth (CC) as the cathode for LIBs, which is performed to slow down the dissolution of Mn and the Jahn–Teller effect of LiMn2O4 during the reaction process. The as‐prepared NLMO NWAs/CC electrode delivers a high capacity of 113.27 mAh g−1 at a current density of 1 A g−1, and can also have a capacity retention rate of 81% after 500 cycles at 10 A g−1, both higher than that of pure LiMn2O4. The results of density functional theory simulation demonstrate that the Ni‐doped LiMn2O4 can significantly decrease the bandgap and Li ions diffusion barriers. A quasi‐solid‐state FARLIB is successfully constructed by using NLMO NWAs/CC as the positive electrode and rugby‐shaped NaTi2(PO4)3/CC as the negative electrode, exhibiting remarkable electrochemical performance and flexibility. These results offer a new opportunity for developing high‐performance FARLIB. [ABSTRACT FROM AUTHOR]

Lightweight high-performance electromagnetic interference (EMI) shielding materials with excellent thermal conductivity and outstanding EMI shielding performances are highly satisfactory for modern integrated electronic and telecommunication systems in the fields of military, aerospace, smart and wearable electronics, and artificial intelligence. Herein, we prepared a cellular MXene@silver nanowire (Ag NW) composite film by a simple vacuum-assisted filtration process induced by potassium ions and freeze-drying after rapid pre-freezing with liquid nitrogen. The construction of the cellular structure can effectively improve the shielding effectiveness. Upon introducing the Ag NWs in the system, the interconnection networks were constructed for the MXene@Ag NW composite film, which significantly improved the electrical and thermal conductivity, further enhancing EMI shielding performance. The composite film with 80 wt% Ag NWs can deliver a high conductivity of 1245 S cm−1, ultrahigh EMI shielding efficiency (SE) of 81.11 dB in the X-band, and a high thermal conductivity of 26.19 W m−1 K−1. The prepared MXene@Ag NW cellular composite film has the advantages of high shielding efficiency and good thermal conductivity, which has important application value in manufacturing lightweight, high shielding efficiency materials and avoiding heat accumulation of electronic devices. [ABSTRACT FROM AUTHOR]

Due to its excellent mechanical properties and ultra-lightweight, Al-based foam with homogeneous small pore-structures has wide applicational prospects in many industrial fields. However, during the foaming process of molten Al, it is difficult to manipulate the pore structures of the Al-based foam by means of the ALPORAS© production route due to the violent gas-releasing performance of TiH2 as a traditional foaming agent. Herein, we developed the melt-foaming route, that is, using MgCO3/Zn composite powder as a foaming agent instead of TiH2, the Al-based foam with homogeneous small pore-structures (average diameter was about 1 mm) was prepared successfully. Meanwhile, the decomposition model of the MgCO3/Zn composite powder was proposed and further verified experimentally. The decomposition kinetics of the MgCO3/Zn composite powder was also analyzed. Our findings not only shed light on the practical manufacturing of Al-based foam with homogeneous small pore-structures, but provide an insightful improvement for melt-foaming approaches. [ABSTRACT FROM AUTHOR]

Characteristics of deformation-induced transformation under loading dictate the mechanical performance of TRIP (transformation-induced plasticity)-reinforced bulk metallic glass composites (BMGCs), which have shown great potential as engineering materials. Here, we report that the addition of 0.3 at.% Ta in the T i 45 C u 41 N i 9 Z r 5 alloy could induce the formation of uniform glassy composite structure with B2-(Ti,Zr)(Ni,Cu) precipitates. More interestingly, nanosized A2-(Ti,Zr)(Ni,Cu) particles also formed inside B2 grains which effectively impede rapid propagation of martensite plates and lead to the formation of multi-oriented martensites, eventually homogenizing the involved plastic flow during deformation-induced transformation. Consequently, high fracture strength (∼3000 MPa), large plasticity (∼25%) and pronounced work-hardening ability were achieved. Microalloying of Ta not only homogenizes the B2 distribution, but also facilitates formation of multi-orientated martensites during deformation, resulting in simultaneously enhanced strength and plasticity of a Be-free Ti-based BMGC. [ABSTRACT FROM AUTHOR]